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Plains Death Adder (Acanthophis hawkei)

The Plains Death Adder is a short, stout, highly venomous terrestrial snake of northern Australian cracking-soil floodplains and clay plains. It is listed as Vulnerable under the EPBC Act and in the Northern Territory and Queensland, so suitable black-soil plains, floodplain ground cover and deep soil cracks need to be retained and checked before clearing.

Conservation status

Commonwealth, EPBC Act 1999: Vulnerable.

Queensland, Nature Conservation Act 1992: Vulnerable.

Northern Territory, Territory Parks and Wildlife Conservation Act 1976: Vulnerable.

Breeding season

Plains Death Adders mate in October to November and give birth to live young in February to March. Plan clearing carefully from October to March, when mating, developing young, births and concealed snakes in ground cover or soil cracks overlap.

Reproductive mode: Live-bearing, described as viviparous in the conservation advice. Another source describes the species as ovoviviparous.

Litter size: Typically 8 to 24 offspring.

Incubation or gestation: Not recorded.

Size at birth: Not recorded.

Age at maturity: Males mature at about 12 months. Females mature at about 18 to 24 months.

Nest or egg sites: Not applicable for live birth. No specific birthing site is recorded.

Breeding frequency: Males may attempt to breed every year. Females breed every one to two years, depending on prey availability.

Confirm timing locally before works, using recent rainfall and floodplain conditions to identify wet-season movement and dry-season sheltering periods.

  • Mating: Mating generally occurs in October to November. These are the documented peak breeding months.
  • Gravid females: The documents do not provide a gestation length. Females are expected to carry developing young between mating in October to November and births in February to March.
  • Births: Live young are generally produced from February to March. Litters typically contain 8 to 24 offspring.
  • Newborns: Newborns should be most abundant around the documented February to March birth period. The duration of dependence and juvenile emergence timing are not recorded.
  • Active period: Movement is more frequent during the wet season, with individuals moving every 3 to 10 days over a few metres to about 1 kilometre. Wet-season months vary across the range, so the November to April pattern is a planning guide rather than a fixed boundary.
  • Dry season inactivity: Individuals are more sedentary during the dry season than during the wet season. Dry-season timing varies with locality and rainfall, and this species does not have a documented period of complete inactivity.
  • Highest clearing risk: Risk is highest from October to March, covering mating, the inferred period when females carry developing young, and births. Ground cover, leaf litter, loose sand and deep soil cracks can conceal adults and young, so wet-season movement and dry-season sheltering should also be considered when scheduling works.

Identification

The Plains Death Adder is a cryptic ambush snake that may remain partly buried in substrate, with only its head and tail exposed. Detection is difficult, particularly where Cane Toads have reduced local abundance.

Adults are short and stout, with a somewhat flattened triangular head that is distinct from the neck. The dorsal colour ranges from grey to brownish-red, or pale brown to grey, and the body usually has broad or irregular transverse bands. The underside ranges from grey to cream. The lips have conspicuous alternating dark and pale bars.

The tail tapers rapidly to a narrow, worm-like tip. The snake waves this tip to attract prey within striking distance. Adults grow to approximately 70 cm on average and up to about 1.2 m, with females generally slightly larger than males.

Average length: Approximately 70 cm.

Maximum length: Approximately 1.2 m.

Body form: Short and stout, with a triangular head and narrow neck.

Identification: Distinguishing features

The smooth or weakly keeled dorsal scales distinguish the Plains Death Adder from the similar Rough-scaled Death Adder, Acanthophis rugosus. Identification from appearance alone may be difficult where it overlaps with the Northern Death Adder, Acanthophis praelongus, and DNA markers may be needed for reliable separation in some areas.

Do not handle a suspected individual. The species is highly venomous and may remain still when approached because its camouflage and ambush behaviour reduce the likelihood of escape.

  • Record clear photographs from a safe distance, including the head, lip pattern, dorsal bands, tail tip and dorsal scale texture.
  • Obtain expert confirmation where identification affects clearing approval, relocation, incident response or population assessment.

Identification: Field signs and detection

There are no documented species-specific tracks, scats, calls, nests or eyeshine records in the supplied documents. Shed skins may be difficult to assign reliably because the species is similar to other death adders.

Individuals bury themselves in leaf litter, sand or soil cracks and may expose only the head and tail. They are well camouflaged and do not usually startle when approached. The most reliable detection method described is slow driving on roads that cross or run close to suitable habitat, particularly in the early evening. Survey effort may need to be large, with detection rates as low as one individual per 30 to 60 hours of surveying in areas invaded by Cane Toads.

Reported detection method: Slow vehicle surveys on roads near suitable habitat, particularly in the early evening.

Reported detection rate after Cane Toad invasion: As low as one individual per 30 to 60 hours of surveying.

  • Treat all suspected death adders as live and dangerous, and keep workers and machinery clear.
  • Use trained fauna personnel and follow the project snake encounter and emergency response procedure.
  • Inspect suitable ground cover and soil cracks before clearing, but do not place hands or tools into cracks or concealed substrate.

Distribution: National range

The species has a disjunct known distribution across northern Australia. Its precise distribution remains uncertain, and suitable habitat suggests that it may occur more widely than confirmed records indicate.

The known range extends through western Queensland and the Northern Territory, with potential habitat extending across northern Australia into north-east Western Australia. Confirmed or reported populations occur in the Mitchell Grass Downs of western Queensland, the Barkly Tableland on the Northern Territory and Queensland border, and floodplains east of Darwin in the Northern Territory.

In the Northern Territory, known Top End habitat includes the Adelaide, Mary and Alligator River floodplains. In Queensland, the species is associated particularly with the Mitchell Grass Downs and western Queensland cracking-soil plains.

States and territories: Northern Territory and Queensland, with potential range extending into north-east Western Australia.

Estimated extent of occurrence: Approximately 720,000 km².

Estimated area of occupancy: Approximately 233,480 km².

Distribution: Bioregions and strongholds

The species occurs in the Darwin Coastal, Pine Creek, Daly Basin, Mitchell Grass Downs, Gulf Fall and Upland, Mount Isa Inlier, and Davenport Murchison Ranges IBRA bioregions.

Reported Northern Territory conservation areas include Kakadu National Park, Mary River National Park, Djukbinj National Park and Fogg Dam Conservation Reserve. The largest contiguous part of the known range is associated with the Barkly Tableland and Mitchell Grass Downs, much of which is pastoral lease country.

The species can be locally common on productive northern river floodplains where Cane Toads are absent. It is less frequently encountered and probably scarcer on the Barkly Tableland and Mitchell Grass Downs.

Distribution: Population size and trend

The total population size is unknown because individuals are difficult to detect. Monitoring has recorded a substantial decline after Cane Toad arrival at an Adelaide River floodplain site, while a separate Fogg Dam study recorded a small increase over four years. The available advice considers the overall observed effect across monitored populations to be a large decline, although local responses vary.

The species was listed as Vulnerable because Cane Toad invasion is expected to cause a substantial reduction in numbers. The older assessment predicted that Cane Toads could encompass almost all of the species' range by 2030; this prediction should not be treated as a current distribution map.

Population size: Unknown.

Reported decline: An 89 percent reduction in Plains Death Adder numbers over five years was attributed to Cane Toad ingestion along an 11 km Arnhem Highway monitoring section.

Survey limitation: Detection is particularly poor in Cane Toad-invaded areas.

Habitat: Habitat types

The Plains Death Adder is associated with flat, treeless, cracking-soil plains in northern Australia. Suitable habitat can occur on riverine floodplains, alluvial plains, black-soil clay plains and related inland clay systems.

The main habitat is flat, treeless, cracking-soil riverine floodplain and clay plain country. In the Barkly region and western Queensland, suitable habitat includes black-soil plains and Mitchell Grass Downs. In the Top End, suitable sites include the cracking-soil floodplains of the Adelaide, Mary and Alligator Rivers.

A Northern Gas Pipeline assessment mapped suitable habitat across alluvial floodplains, drainage systems, downs plains, inland wetlands, alluvium associated with river and creek flats, and clay plains not associated with current alluvium.

  • Retain intact cracking-soil plains, floodplain ground cover and connected suitable country within and beside the work area.
  • Treat apparently open or sparsely vegetated clay plains as potential habitat where soil cracking and nearby frog or rodent habitat are present.

Habitat: Structural features

Important structural features include deep soil cracks, leaf litter, sand or other loose substrate suitable for partial burial, and ground cover that supports frogs, lizards and small mammals. The species may use emergent vegetation or floating debris during floods.

The species is not associated with trees, tree hollows or rocky refuges in the supplied documents. Its habitat is generally flat and treeless.

Habitat: Elevation and climate

No elevation limits are given in the supplied documents. The species is restricted to northern Australian environments with seasonal wet and dry conditions, and its activity and movement change between those seasons.

Foraging habitat: Diet

The Plains Death Adder is a nocturnal ambush predator. It waits partly buried in suitable substrate and uses its tail tip to lure prey into striking range rather than actively searching for food.

Frogs and lizards make up approximately 95 percent of the diet of young Plains Death Adders. Larger individuals switch to small mammals such as rats, and larger prey is often taken by females because females more commonly attain the larger body size.

The Northern Territory species account also describes the species as a predator of frogs, reptiles and rodents, with larger individuals taking rodents and other small to medium-sized mammals.

Young diet: Frogs and lizards comprise approximately 95 percent of the diet.

Larger individual diet: Small mammals, including rats, and other small to medium-sized mammals.

Foraging habitat: Foraging method

Between movements, the snake buries itself in leaf litter, sand or other substrate and waits with only the head and tail exposed. It undulates the narrow tail tip to imitate prey such as a worm, caterpillar or other defenceless insect.

Cane Toads respond strongly to this lure and may be captured by the snake. The species does not appear able to discriminate reliably between Cane Toads and native frogs, making this specialised feeding behaviour a major conservation risk.

  • Retain ground cover and soil structure that provide concealed ambush positions.
  • Avoid unnecessary disturbance of wet-season frog habitat and drainage lines that support prey.
  • Manage artificial waterpoints and grazing so that ground cover and prey habitat are not progressively reduced.

Foraging habitat: Foraging range and movement

Radiotracking indicates that individuals are nomadic and do not have a definable home range. During the wet season, they move every 3 to 10 days, travelling from a few metres to approximately 1 km in apparently random directions. Movement is less frequent during the dry season.

Wet-season movement interval: Every 3 to 10 days.

Wet-season movement distance: From a few metres to approximately 1 km.

Home range: No definable home range has been identified.

Breeding habitat: Breeding biology

The Plains Death Adder is viviparous and gives birth to live young. The supplied documents do not identify a separate nest site, so breeding habitat is best understood as suitable cracking-soil habitat with shelter and adequate frog, lizard and mammal prey.

Mating season: Generally October to November.

Birth season: Generally February to March.

Reproductive mode: Viviparous, producing live young.

Litter size: Typically 8 to 24 offspring.

Male maturity: Approximately 12 months, or during the first year.

Female maturity: Approximately 18 to 24 months.

Female breeding frequency: Every one to two years, depending on prey availability.

Male breeding frequency: Males may attempt to breed every year.

Life expectancy: Approximately 10 years.

Generation length: 3 to 5 years.

Breeding habitat: Breeding habitat requirements

Breeding occurs within the species' wider floodplain and cracking-soil plain habitat. The documents do not describe a nest, den, egg-laying site or specific birthing microhabitat.

For project planning, retain connected suitable plains, soil cracks, ground cover and prey habitat through the October to March breeding and birth period. Avoid assuming that a cleared strip is unused simply because no snake is seen during a daytime inspection.

  • Schedule unavoidable clearing outside the breeding and birth period where practicable.
  • Complete pre-clearing searches across cracking-soil plains and floodplain ground cover before machinery enters.
  • Keep fauna spotter catchers alert for concealed snakes in leaf litter, sand, soil cracks and debris.

Sheltering habitat: Refuges and concealment

The species shelters in or beneath ground-level substrate rather than in trees. Its camouflage and use of soil cracks make it easy to overlook during standard clearing inspections.

Between movements, individuals bury themselves among leaf litter, sand or other substrate and adopt an ambush position. During the dry season they may retreat into deep soil cracks.

During floods, individuals may float in debris or rest on emergent vegetation. These flood refuges may be temporary and can be difficult to inspect safely.

  • Inspect leaf litter, loose sand, debris and deep soil cracks before clearing or grading.
  • Do not put hands, feet or tools into cracks, cavities or concealed debris.
  • Retain undisturbed ground cover and soil cracking where it can be avoided by the works.

Sheltering habitat: What is not documented

The supplied documents do not provide dimensions for shelter sites and do not report use of burrows, tree hollows, rock shelters, nests or communal dens. They also do not provide a reliable method for assigning shed skins to this species.

Threats: Cane Toad poisoning

Cane Toad poisoning is the main identified threat. On development sites, clearing, loss of ground cover, road mortality, trench entrapment, altered drainage and inappropriate fire can add local pressure, particularly where works intersect cracking-soil plains and floodplains.

The species' tail-luring behaviour attracts Cane Toads more strongly than native prey. The snake does not appear able to discriminate between them, and ingestion of Cane Toad toxins typically causes death. Large numbers may die when Cane Toads arrive in an area.

Cane Toads can also be favoured by artificial waterpoints and increased grazing pressure, which may reduce ground cover and improve conditions for toad spread.

  • Include Cane Toad controls and monitoring in site environmental plans where the species occurs or suitable habitat is present.
  • Report dead or incapacitated death adders and Cane Toad activity through the project's fauna incident process.
  • Do not rely on national parks or other reserves to remove the Cane Toad risk.

Threats: Clearing and construction

Clearing of flat, treeless cracking-soil plains can remove ambush sites, soil cracks, leaf litter and prey habitat. Linear works can divide connected habitat and increase vehicle movements across areas where snakes may move between floodplain and clay plain habitat.

The species is difficult to detect and may remain buried or still when approached. A negative search result therefore does not demonstrate absence.

Example project habitat extent: A Northern Gas Pipeline assessment identified approximately 820.1 ha of potential habitat within its project footprint, including 206 km of habitat along the construction right of way.

  • Map and avoid suitable cracking-soil plains, floodplain ground cover and deep soil cracks wherever practicable.
  • Use pre-clearing inspections by trained fauna personnel before vegetation or soil disturbance.
  • Keep open trenches, pits and other excavations covered or provide escape ramps and inspect them at least daily, because a ground-dwelling snake may become trapped.
  • Use low-speed vehicle controls on roads and access tracks crossing suitable habitat, especially during evening and wet-season movement periods.
  • Maintain habitat links across linear infrastructure through suitable crossing points and minimised clearing widths.

Threats: Grazing, fire and ground cover

Overgrazing and fire regimes that produce large-scale wildfires can reduce ground cover and prey availability. Artificial waterpoints may increase total grazing pressure rather than distribute existing stock pressure, and may also favour Cane Toad spread.

Loss of ground cover reduces concealment and refuges for an ambush predator that relies on substrate and camouflage.

  • Control stock access and grazing pressure around known or potential populations.
  • Avoid large-scale, unseasonal fires in suitable habitat and prepare fire plans that retain ground cover and refuge areas.
  • Prevent unnecessary removal of leaf litter, fallen debris and soil structure outside the approved disturbance footprint.

Threats: Hydrology and flooding

Large, unseasonal floods may reduce the availability of native rats and frogs, although the supplied advice describes these events as rare and usually localised. Flooding can also move snakes in debris or onto emergent vegetation.

Changes to floodplain drainage, water availability or wetland hydrology may alter frog and rodent prey habitat, but species-specific thresholds are not provided.

  • Avoid blocking, concentrating or diverting natural floodplain flows where practicable.
  • Manage sediment, contaminants and water quality so that frog habitat and other prey resources are not degraded.
  • Inspect debris, emergent vegetation and floodwater margins safely after flood events before machinery or vehicles enter.

Threats: Predators, roads and other pressures

Birds, goannas and other snakes prey on Plains Death Adders. Road and vehicle strike is a plausible project risk because the species may cross roads, and the recommended detection method relies on road transects, but the supplied documents do not quantify road mortality.

Disease is not identified as a threat in the supplied documents. No species-specific disease controls are therefore provided beyond standard hygiene and incident reporting for wildlife handling.

  • Apply low vehicle speeds and fauna awareness controls on roads near suitable habitat.
  • Do not move snakes between sites unless authorised under the relevant wildlife permits and project procedure.
  • Record all captures, injuries, deaths and relocations to support monitoring of local impacts.

Survey methodology: 1. Map and inspect potential habitat

Plains Death Adders are cryptic, nocturnal ambush snakes that are difficult to detect, especially after cane toads have arrived. Survey design should combine habitat assessment with slow road-based searches and project-specific advice from the relevant wildlife authority.

Identify flat, treeless cracking-soil plains, black-soil clay plains, riverine floodplains and associated deep soil cracks before selecting survey routes.

Use aerial imagery and land-system mapping, then ground-truth the mapped habitat. Mark drainage lines, floodplain margins, deep cracks, refuge areas and connected areas of suitable habitat.

Record cane toad presence, grazing intensity, ground-cover condition, recent fire and access constraints because these factors affect habitat quality and detection.

Known habitat: Flat, treeless cracking-soil floodplains and clay plains in northern Australia.

Known project example: A 2016 assessment mapped 206 km of potential habitat along a construction corridor and approximately 820.1 ha of suitable habitat within the project footprint.

Survey methodology: 2. Slow road searches at night

Use slow vehicle searches on roads that cross or run close to suitable habitat, particularly during the early evening when animals may be moving across the road surface.

Search during the wet season, when individuals move more often. Individuals may move from a few metres to 1 kilometre every 3 to 10 days during the wet season, while movement is less frequent in the dry season.

Use experienced observers and record the route, start and finish times, weather, recent rainfall, road conditions, cane toad presence and all target-species observations.

Treat a nil result cautiously. In areas invaded by cane toads, detection rates may be as low as one Plains Death Adder per 30 to 60 hours of surveying.

Movement period: Wet season.

Movement interval: Every 3 to 10 days, with movements from a few metres to 1 kilometre.

Low detection rate reported after cane toad invasion: One individual per 30 to 60 hours of surveying.

Survey methodology: 3. Search suitable habitat and road edges

Walk or drive slowly along accessible roads, tracks and habitat edges that intersect cracking-soil plains, using a search pattern that covers both the road surface and adjacent refuge areas.

Search around leaf litter, sand, deep soil cracks and low ground cover where an ambush-positioned snake may be concealed.

Schedule repeat searches rather than relying on a single visit, because the species is nomadic and does not have a definable home range.

Do not use road searching alone to clear an area. Combine it with a pre-clearance inspection and a fauna management procedure for machinery works.

Ambush position: The snake buries itself in substrate such as leaf litter or sand, exposing mainly its head and tail.

Dry-season refuge: Individuals may retreat into deep soil cracks.

Survey methodology: 4. Use targeted habitat assessment where detection is unlikely

Where the project cannot support reliable night searches, document the extent and quality of potential habitat instead of treating a nil survey result as proof of absence.

Use high-resolution aerial imagery followed by field ground-truthing to validate cracking-soil plains, floodplains and connected habitat.

Seek advice from the relevant state or territory wildlife agency where targeted surveys are unlikely to detect the species. A 2016 project did not undertake targeted surveys after agency advice because detection probability was low, but still assessed the species as likely to occur based on habitat.

Record the survey limitations, mapped habitat, search effort and basis for the occurrence assessment in the project environmental records.

Survey methodology: 5. Minimum effort and reporting

  • Use a documented survey plan that states the habitat searched, survey dates, start and finish times, observers, vehicle or walking method, weather, rainfall, cane toad observations and the reason for selecting each route.
  • Repeat night searches through suitable wet-season conditions where access and safety allow, and explain any departure from the planned effort.
  • Use suitably experienced ecologists or fauna spotter catchers who can distinguish the Plains Death Adder from similar Acanthophis species, noting that DNA marker analysis has been identified as useful for separating it from the Northern Death Adder.
  • Submit confirmed records, photographs, coordinates and detection effort to the relevant state or territory wildlife database, and provide records required by project approvals and the Australian Government species database.
  • Report nil results with equal detail, including the area of mapped habitat and the total search effort, because this species has a low detection probability.

Before habitat disturbance: 1. Avoid and minimise habitat disturbance

Plan works around the species' habitat and very low detectability. A suitable habitat assessment does not replace approvals, pre-clearance controls or a fauna management plan.

Avoid clearing flat, treeless cracking-soil plains, riverine floodplains, black-soil clay plains and deep-crack refuge areas wherever practicable.

Retain connected areas of suitable habitat, including habitat outside the immediate disturbance footprint, because the species uses broad areas and has no definable home range.

Keep construction access, vehicle movements, laydown areas and spoil stockpiles out of retained floodplain and cracking-soil habitat where practicable.

Minimise changes to drainage, floodplain inundation, ground cover and prey habitat. Do not create new water points unless the environmental assessment has considered their potential to increase grazing pressure and favour cane toads.

Project example: A Northern Gas Pipeline assessment treated a potential population near the species' known range limit as important for maintaining genetic diversity.

Before habitat disturbance: 2. Confirm approvals and responsibilities

Check whether the proposed action may significantly impact this EPBC Act Vulnerable species and obtain project approval or complete the required referral process before works begin.

Confirm the applicable Northern Territory or Queensland requirements, including any state wildlife permits, handling authorities and conditions attached to the development approval.

Appoint an appropriately authorised fauna spotter catcher and nominate the ecologist or wildlife carer responsible for identification, handling, treatment and release decisions.

Include the species, mapped habitat, survey limitations, cane toad risk, stop-work triggers, reporting pathway and rehabilitation requirements in the fauna management plan.

Commonwealth status: Vulnerable under the EPBC Act.

State status in supplied records: Vulnerable in the Northern Territory and Queensland.

Before habitat disturbance: 3. Stage and time the works

Schedule clearing outside the wet-season movement period where practicable, while recognising that dry-season animals may be concealed in deep soil cracks and will not necessarily be easier to detect.

Stage clearing in small, manageable sections so the fauna spotter catcher can inspect each work area immediately before disturbance and machinery can stop quickly.

Avoid commencing earthworks during flooding, heavy rain or conditions that prevent safe inspection of cracking soils, floodplain margins and access routes.

Brief all operators on the species' appearance, its highly venomous nature, the no-handling rule for unauthorised personnel and the procedure for a snake sighting.

Before habitat disturbance: 4. Prepare the disturbance area

Complete a pre-clearance inspection of the approved work area and access tracks immediately before clearing, with particular attention to leaf litter, sand, deep soil cracks, floodplain edges and areas with intact ground cover.

Clearly mark the approved clearing boundary, retained habitat, exclusion zones, access routes, stockpile areas and any habitat features to be retained.

Install exclusion fencing only where it can be maintained, inspected and designed to avoid trapping snakes or blocking movement into unsuitable areas.

Remove or repair hazards that could trap a snake, including open pits, uncapped pipes, poorly secured mesh, uncovered trenches and deep construction materials.

During habitat disturbance: 1. Apply daily work controls

The Plains Death Adder is highly venomous and may remain concealed until machinery or people are close. The fauna spotter catcher must have authority to stop work and must control the response to every suspected sighting.

Inspect the active work area, access tracks, spoil areas, open trenches and retained habitat at the start of each workday and after any work break that could allow an animal to enter.

Maintain a fauna spotter catcher at the active clearing front and position the person where the operator can see and hear the stop-work signal.

Keep vehicles to approved tracks and control speed on roads crossing or running close to suitable habitat, particularly during evening movements.

Keep trenches, pits and pipes covered or fitted with escape measures when not actively being worked, and inspect them before backfilling or moving them.

Do not leave food waste, water containers or other materials that could attract frogs, rodents or cane toads into the work area.

During habitat disturbance: 2. Coordinate the spotter catcher and machinery

The spotter catcher must walk the area immediately ahead of clearing equipment and direct the operator to stop before any suspected snake, deep crack, log, rock pile or other refuge is disturbed.

Use staged clearing that moves fauna towards retained habitat only where the movement path is safe, connected and approved in the fauna management plan.

Do not assume that a cleared strip is free of snakes after one inspection. Reinspect the next work section as machinery advances and after spoil, vegetation or debris is moved.

Stop the machine before the spotter catcher approaches a suspected animal, because vibration, movement and dust can make identification and safe capture more difficult.

During habitat disturbance: 3. Manage habitat features and excavations

Retain intact cracking soils, deep soil cracks, leaf litter, ground cover and floodplain features outside the approved footprint.

Have the spotter catcher inspect logs, rocks, debris, sand piles, soil cracks, pipes, culverts and open excavations before they are moved, filled or covered.

Do not place removed logs, rocks or spoil against retained habitat where they could block movement or create a new trapping hazard.

Treat flooded work areas and floating debris as potential fauna habitat, noting that the species may float in debris or rest on emergent vegetation during floods.

During habitat disturbance: 4. Respond to a suspected or confirmed animal

Stop work immediately, keep people and machinery clear, and establish a safe exclusion zone around the animal.

Do not touch, corner, chase, tease or attempt to catch a Plains Death Adder unless authorised and trained under the project fauna procedure.

Confirm identification from a safe distance where possible, using photographs and an experienced ecologist or authorised handler rather than relying on an untrained visual identification.

If relocation is authorised, use an appropriately qualified handler and place the animal in nearby retained habitat that matches the approved release conditions, without moving it unnecessarily far from the disturbance area.

If the snake is injured, contact the nominated wildlife carer or veterinarian and follow the authority's instructions for secure transport. Do not attempt first aid or treatment in the field.

Treat any suspected bite as a medical emergency and activate the project emergency response immediately.

Species risk: The Plains Death Adder is highly venomous.

During habitat disturbance: 5. Stop work and record the event

Stop work for any confirmed or suspected Plains Death Adder sighting until the animal has moved or an authorised person has completed the response.

Stop work if a snake is found in a trench, pipe, stockpile or other trap, and keep the feature isolated until it has been inspected and made safe.

Stop work if clearing extends beyond the approved boundary, if mapped cracking-soil habitat differs materially from the assessment, or if repeated fauna hazards cannot be controlled under the fauna management plan.

Record the date, time, coordinates, habitat, weather, activity, identification evidence, photographs, handling or relocation details, injury status, personnel involved and the work response.

Notify the project environmental officer and the relevant approval agency where required, and submit a confirmed record to the relevant state or territory wildlife database.

After habitat disturbance: 1. Complete post-clearance checks

Post-clearance work must check that animals have not been trapped and that retained habitat remains connected and safe. Monitoring should be scaled to the amount of suitable habitat disturbed and the conditions of approval.

Inspect the cleared area, retained habitat edges, trenches, pits, pipes, culverts and spoil areas after clearing and before the next construction phase.

Check that exclusion fencing, covers and escape devices remain effective and have not created barriers or traps for snakes.

Search for live animals, carcasses, tracks, shed skins and signs of cane toad activity, and record the result with the same detail as the pre-clearance inspection.

Backfill or make safe all temporary excavations and remove unused materials that could trap or conceal a Plains Death Adder.

After habitat disturbance: 2. Monitor retained and restored habitat

Monitor retained cracking-soil plains, floodplain margins and connected habitat during the wet season and after major construction disturbance, using repeat night searches where safe and authorised.

Compare encounter rates, cane toad presence, ground cover and habitat condition with the pre-construction records, while recognising that a nil result is not evidence of absence.

Inspect areas where the project has altered drainage, ground cover, access or grazing patterns, and correct avoidable impacts under the environmental management plan.

Continue monitoring for the period required by project approval, the fauna management plan or advice from the relevant wildlife authority.

Reference monitoring effort: A five-year monitoring study after cane toad arrival recorded an 89 percent reduction in Plains Death Adder numbers along an 11 km section of the Arnhem Highway.

After habitat disturbance: 3. Close out and report

Provide the environmental officer and approval agencies with the final cleared area, retained habitat area, fauna incidents, relocations, injuries, mortalities, survey effort and monitoring results.

Update the species risk assessment if the work finds new records, previously unmapped habitat, unexpected mortality or evidence that cane toads have entered retained habitat.

Maintain exclusion fencing, trench controls, access controls, weed controls and fire controls until the site is stable and the rehabilitation area has been formally handed over.

Apply any required offset, conservation payment, habitat protection or compensatory action specified by the approval.

Rehabilitation actions: 1. Reinstate suitable ground habitat

Rehabilitation should restore the flat, open, cracking-soil habitat used by the Plains Death Adder and maintain access to connected floodplain and clay-plain habitat. Set measurable completion criteria before works begin.

Recontour disturbed ground to match surrounding floodplain and clay-plain levels, avoiding barriers that interrupt shallow overland flow or create erosion channels.

Replace suitable local soil and surface material so that cracking soils can reform where they were removed or compacted.

Re-establish native ground cover that provides concealment and supports frogs, lizards and small mammals, while retaining open, treeless conditions where those conditions are characteristic of the site.

Reinstate suitable leaf litter, sand and other natural surface cover without creating piles that could trap snakes or obstruct movement.

Rehabilitation actions: 2. Restore habitat connections and fauna features

Remove temporary roads, laydown areas, fencing and stockpiles that are no longer required, and reconnect the rehabilitated area with retained cracking-soil plains and floodplain habitat.

Retain or replace naturally occurring logs, rocks and other ground refuges only where they are characteristic of the local habitat and will not create a fauna trap.

Do not plant dense trees or shrubs across naturally treeless floodplain or clay-plain habitat.

Do not install nest boxes for this snake. Focus rehabilitation on cracking soils, ground cover, prey habitat and safe movement routes.

Rehabilitation actions: 3. Control weeds, grazing, cane toads and fire

Control weeds that reduce native ground cover or alter the structure of the cracking-soil plain, using methods approved for the site and nearby waterways.

Manage stock access and artificial watering points so rehabilitation is not degraded by increased grazing pressure or conditions that favour cane toad spread.

Apply the approved fire management strategy so fire does not remove ground cover across large areas or reduce prey availability at the same time.

Monitor cane toad occurrence and follow the relevant cane toad management arrangements, noting that broad-scale control has not been effective in the supplied conservation advice.

Rehabilitation actions: 4. Measure rehabilitation success

Set completion criteria for surface stability, re-formed cracking soils, native ground cover, absence of construction hazards, weed cover, grazing pressure and continuity with retained habitat.

Inspect rehabilitation areas after wet-season rainfall and during the dry season, because the species uses the area differently across seasons and may retreat into deep cracks during dry conditions.

Use repeat night searches on safe nearby roads and retained habitat, together with habitat-condition monitoring, to assess whether the rehabilitated area is being used.

Report unsuccessful rehabilitation, new cane toad records, fauna mortality and any need for additional earthworks, weed control, grazing management or fire management.

Relevant life-history timing: Breeding generally occurs from October to November, and live young are produced from February to March.

Generation length: Approximately 3 to 5 years.

Sources